1. Field of the Invention
The present invention pertains to a methods and apparatus for endoscopic and open surgery and, more particularly, to various end effectors of a surgical device that are offset from an axis and methods of manipulating these end effectors.
2. Discussion of the Related Art
Various steps are accomplished in both open surgery and endoscopic surgery. Generally the multiple steps require various operating instruments. "Open surgery" refers to surgery wherein the surgeon gains access to the surgical site by a relatively large incision and "endoscopic surgery" refers to minimally invasive surgery wherein the surgeon gains access to the surgical site via one or more portals through which endoscopes are introduced to view the surgical site and through which instruments having "end effectors", such as forceps, cutters, needle holders, cauterizers, and the like, are introduced to the surgical site.
The performance of an endoscopic procedure typically involves creation of one or more puncture sites through a wall of an anatomical cavity using a penetrating instrument including an obturator, such as a trocar, disposed within a portal sleeve. After the penetrating instrument has penetrated into the anatomical cavity, the obturator is withdrawn leaving the sleeve in place to form a portal in the cavity wall for the introduction of instruments such as endoscopes, scissors, forceps, needle holders and the like into the anatomical cavity.
The various end effectors at the distal end of the instrument are manipulated by the surgeon using controls disposed at the proximal end of the instrument. Of course, it is desirable to move the end effectors through various paths, depending on the step being performed. Traditionally, this was accomplished by moving the entire end of the endoscopic instrument. However, recently it has been proposed to provide a plurality of end effectors on a single endoscopic instrument to minimize the number of puncture sites and thus reduce the risk and healing time associated with endoscopic surgery. See applicant's concurrently filed patent applications entitled "Suturing Instrument with Multiple Rotatably Mounted Offset End Effectors and Method of Using the Same" and "Surgical Instrument with Multiple Rotatably Mounted Offset Needle Holders and Method of Using the Same", the disclosures of which are incorporated herein by reference.
When a plurality of end effectors are incorporated into a single endoscopic device it is desirable to move the end effectors individually with respect to one another without necessarily moving the entire device. Also, even in single end effector devices, it is often desirable to move the end effector through a predetermined path, such as an arc or the like during an operative step, without repositioning the entire endoscopic device.
Of course, it is also generally desirable to minimize the size of each puncture site. Further, in order to permit operations on a wide range of tissue sizes, it is desirable to provide a wide range of relative movement between the end effectors. These objectives, minimal number/small size punctures and wide range of relative movement, are seemingly contradictory. Conventional devices have not achieved the above-noted objectives.
U.S. Pat. No. 5,582,617 discloses an endoscopic instrument having an end effector that can move from a position within the diameter of the barrel of the device to a position outside the diameter. However, this device must pivot about an axis that is transverse to the axis of the barrel and an axis that is coincident with the axis of the barrel and thus requires a complex movement and linkage to accomplish the disclosed functions. Accordingly, this device falls short of providing an end effector that can be utilized over a large working span for a wide range of applications.